Method and apparatus for packaging loose aggregate materials



Aug. 9, 1966 H. D. ONEAL EI'AL METHOD AND APPARATUS FOR PACKAGING LOOSEAGGREGATE MATERIALS INVENTORS. Hfl/EEYD. O/VEAL BY P055273 WHEEL E2.

HUU/PIVE 2 Sheets-Sheet 1 Filed Jan. 24, 1963 Aug. 9, 1966 H. D. ONEALET AL 3,265,098

METHOD AND APPARATUS FOR PACKAGING LOOSE AGGREGATE MATERIALS 2Sheets-Sheet Filed Jan. 24, 1963 v QMkQMms him \sM INVENTORS.

mllllllllllllllllIIHIIIIIIIIIZ;

Z L z WE w W H 95. mm M g m United States Patent Office 3,255fi98Patented August S, 1966 3 265,098 METHOD AND APPARATUS FOR PACKAGHNGLOOSE AGGREGATE MATERIALS Harry D. ONeal, Seekonk, Mass, and Robert B.Wheeler, Bellaire, Tex., assignors to St. Regis Paper Company, New York,N.Y., a corporation of New York Filed Jan. 24, 1963, Ser. No. 253,556 9Claims. (Cl. 141-5) This invention pertains to methods and apparatus fordispensing and packaging loose, aggregate materials having a particlesize, such as to permit of dispensing by flow of air or other gas underpressure, but nevertheless such as to permit of forming an efiective gasseal under a hydrostatic head thereof of substantial pressure. Suchmaterials are generally characterized by a granular or pellet-likeparticle size, and are exemplified by such materials as dry sand, drysand-cement gravel aggregates, plastic pellets or gravel, seed corn,peas, shelled beans, etc.

The invention pertains more particularly to improvements in so-calledforce flow packers, wherein the aggregate material is dispensed from abin through a discharge spout thereof and into a packaging container,such as a paper bag, by the injection of gas, such as air, underpressure in the bin, and under conditions such that the bin except forthe spout outlet, is otherwise effectively sealed against the outeratmosphere during the discharge, whereby the material is forcefullydischarged through the spout by the pressurized air flow either withoutor with fluidation of the material.

The invention has as one of its objectives, a simplification ofapparatus and methods heretofore deemed necessary for dispensing andpackaging loose aggregate materials of the character aforesaid, wherebyapparatus components and manipulative operations are eliminated ascompared to practices of the prior art.

The invention provides as another of its objectives apparatus of thecharacter aforesaid having greatly increased operating life withoutrepairs, and reduced downtime for repairs and replacement of parts ascompared to prior such apparatus.

The invention provides as still another of its objectives, apparatus asaforesaid which is far superior to existing devices for the packaging ofabrasive materials or pelletized material of -a particle size such astends to jam and block mechanical closure members of existing packagingmechanisms.

These and other advantages of the apparatus and methods of the inventionas compared to packaging mechanisms and techniques heretofore utilizedfor the above stated, purposes, will become apparent as the descriptionproceeds.

Force flow packers of a type which have heretofore proved highlyeffective for dispensing a Wide variety of loose aggregate materials aredescribed in a copending application of O. R. Titchenal and I. H.Stockwel, Serial No. 810,465, filed May 1, 1959. This apparatus in oneembodiment, comprises a vertical dispensing or packer bin, usuallycylindrical, of a length exceeding its width, and having a dischargespout at the base, a fluidizing air pad adjacent the spout, valveconnected to a compressed source, which is also valve connected to apipeline penetrating the bin sidewall near the top and terminatingwithin the bin preferably in a disseminator or perforated tubular memberextending axially of the bin for a substantial distance fordisseminating the air flow throughout the mass of material. The bin isclosed oif at the top except for a restricted aperture, opening into thebase of a supply bin disposed above the packer bin to provide an infeedpassage for periodically charging the aggregate material from the formerinto the latter by gravity feed. The discharge spout and infeed passagesare provided with electrically or pneumatically actuated mechanicalclosures for shutting off or releasing the flow of material. Means arealso provided for venting the packer bin to atmospheric exhaust.

According to one mode of operation, with the packer bin vented toatmosphere and the compressed air supply shut off, the infeed closure isopened to discharge the packer from the supply bin while maintaining thedischarge spout closed. The infeed closure and bin vent are then shut,and with the compressed air supplied to the fluidizing pad anddisseminator, the spout is opened to discharge the material into a bagor other container afiixed to the spout. When the bag is filled to apreselected weight, the spout is closed, the air supply shut off, andthe packer bin again vented to exhaust, and the bin recharged asaforesaid.

Now We have discovered in accordance with the present invention, thatfor packaging loose aggregate materials of the character and having theproperties set forth above, namely, those which may be dispensed bycompressed air flow but which nevertheless compact to a sufficientdensity under a hydrostatic head of a hundred pounds or so, so as toprovide an effective air or gas seal over a restricted aperture ofexposure, that it is not necessary to effect mechanical closure of theinfeed duct between the supply and packer bins during discharge of theaggregate material from the latter through the discharge spout, providedthe following con ditions are met. That is to say, 'we have found thatthe need for mechanical closure of the infeed passage between thestorage and packer bins may be eliminated, if the infeed duct passage ismade of sufficiently small aperture and of sufiicient length, and ifconcurrently therewith the disseminator is so dimensioned or positionedthat its lower end extends down substantially to the level of thedispensing bin discharge spout. We have found that under theseconditions the loose aggregate material itself forms and maintains aneffective air seal in the infeed duct, while the packer bin is beingdischarged. The apparent reason for this is that during discharge of thepacker bin contents into the packaging container, it is easier for thecompressed air injected into the packer bin, to flow from thedisseminator to the discharge spout than it is for the air to flow fromthe disseminator back up through the material bed into the supply binabove. Apparently also the upsurge of air under pressure from thedisseminator combined with the compacting action of the hydrostatic headof material in the supply bin, so compacts the material within the ductas to plug it during discharge from. the spout.

It was found by experiment, that during discharge of the packer bin theaggregate material automatically bridges across the infeed duct, andthereby (prevents material in the storage bin from falling into thepacker bin during discharge of the latter. It Was further observed thatshortly after the air supply to the packer bin is shut oft and theiatter vented to exhaust, the bridge of aggregate material in the infeedduct collapses, permitting the material to fall from the supply bin intothe packer bin and thus refill the latter. As a necessary condition forthis observed operation, it was found that a sufficient hydrostatic headof the aggregate material was required to be maintained in the supplybin, on the order of about to 300 pounds over the cross-sectional areaof the infeed duct, depending on the material being packaged.

Thus according to our observations the combination of factors apparentlyconducive to formation of the material bridge across the infeed duct andconsequent air seal produced thereby are: the packing effect of thehydrostatic head of the aggregate material in the supply bin, therestricted aperture. of the infeed duct and the use of a relatively longdisseminator, the lower end of which terminates reasonably close to theopening with the packer bin discharge spout. The length of the infeedduct also appears to be a factor, in that it must be of sufificientlength to permit formation of the material bridge therein.Exemplification of these apparent controlling factors will be givenbelow.

We have observed as a further object of our invention, that thefiuidizing air pad at the base of the packer bin is not required, butmay be used to advantage under certain conditions of operation.

Having thus generally described our invention, reference will now be hadfor a more detailed description of the above and other features, to theaccompanying drawings, wherein:

FIG. 1 is a more or less schematic or diagrammatic view in elevation,and partly in longitudinal section of a bag filling apparatus accordingto the invention.

FIGS. 25, inol., are similar views illustrative of successive stages ofthe bag filling operations.

FIG. 6 is a fragmentary showing in elevation of the upper portion of theFIG. 1 apparatus, illustrative of a modified form of infeed ductinterconnecting the supply and packer bins.

FIG. 7 is a fragmentary view in elevation of the base portion of theFIG. 1 apparatus, illustrating the addition thereto of a fluidizing airpad and appurtenant components.

FIG. 8 is a further fragmentary detail in elevation of the upper portionof the FIG. 1 assembly, showing the addition to the infeed air duct of amechanical closure member for purposes hereinafter stated.

Referring to FIG. 1, the apparatus shown comprises a vertical packer ordispensing bin 10 of cylindrical, rectangular or other polygonalcross-section, of a length exceeding its transverse dimension. The binterminates at its base in a discharge outlet 11, connected through aflexible coupling 12 to a spout 13, which is inserted in the sleeve of avalve sleeve type bag 14, the bag being secured to the spout by areleasable clamp 15. The flexible coupling 12 may be pinched tomechanical closure, as at 16, by means of a releasable clamp 17. Clamps15 and 17 may be pneumatically, electrically or otherwise actuated.

A pipe section 20 extends through the sidewall 21 of bin 10, preferablythrough. the upper half thereof and is connected within the bin to thetop of a tubular disseminator 22, of sheet metal, plastic or the like,the cylindrical wall portion of which is provided with a series ofholes, as at 23, disposed therealong and thereabout, for disseminatingair or other gas injected under pressure into the disseminator via thepipeline 20. The disseminator may be installed in sections, as at 22a,and as thus extended to a desired or required overall length. Thedisseminator is preferably positioned substantially coaxial with the bin10 as shown, and its lower end extends down to a level close to that ofthe discharge outlet 11.

The pipe section 20 terminates exteriorly of the bin 10, in a valve 24,which is positionable for connecting the pipe section 20 either to apressure line 25 extending to a source of compressed air, oralternatively to an atmosphenic exhaust outlet 26.

The bin 10 is closed off at the top by a cover plate which is centrallyapertured, as at 31, for reception of a closely fitting infeed duct 32,which projects into bin 10 below the cover 30, for a substantialdistance, as at 33, as discussed below. The infeed duct terminates atits upper end in a tapered base 34, of a supply bin mounted above thepacker bin 10 as shown.

In a specific embodiment of the apparatus, operated in accordance withthe invention as above described, the packer bin 10 was cylindrical andof diameter 14 inches and height 5 feet. The infeed duct 32 was likewisecylindrical and of a length 12.5 inches, of a diameter 6 inches,

and projected 6.5 inches into bin 10 below the cover 30 thereof. Thedisseminator 22 was of a length 30 inches and diameter 5 inches. Itslower end was 6 inches above the base of the packer bin. Air wassupplied over line 25 at pressure of 10 p.s.i.

Referring nowto FIGS. 25, incl., for a description of the operation ofthe FIG. 1 apparatus in filling bag 14 with loose aggregate materialfrom the packer or dispensing bin 10, the operating cycle is as follows:Assuming the apparatus initially in the completely empty condition ofFIG. 1, the flexible coupling 12 in the packer bin discharge outlet ispinched off by the closure clamp 17, and the valve 24, actuated toexhaust as indicated by the arrow. A supply of the loose aggregatematerial is changed, as at 50, into the supply bin 35. During thecharging the material will fall through the infeed duct 32 into thepacker bin 10 until the latter is filled, as at 51. Continued loadingwill then progressively fill the supply bin 35 with the material, as at52, this filling being continued until the supply bin is filled to alevel 53, such that the hydrostatic head of the material over the areaof the infeed ducts is on the order of about -300 pounds, depending onthe material. With the apparatus exemplification above given, this wouldbe on the order of about 3-10 p.s.i. over the duct area.

The bin valve 24 is now actuated to connect the disseminator pipeline 20to the air infeed pressure line 25, as shown by the arrow on FIG. 3, andthe bin discharge spout clamp 17, released, as also shown in FIG. 3. Theloose aggregate material in the packer bin 10. will thereupon startflowing through the bin discharge outlet 11 and spout 13 into the bag14, under the combined action 7 of gravity and the flow of air underpressure from the disseminator 22.

The outward fiow of air from the disseminator 22 will be somewhat asindicated by the arrows of FIG. 3. Some will flow downward as shown tofacilitate discharge of the loose aggregate through spout 13 of thepacker bin; while some of the air will flow upward toward the infeedduct 32 as indicated, tending thereby to prevent further discharge ofthe aggregate 52 from the supply bin into the packer bin. Due to thecombined action of the upsurge of air against the infeed duct and thepacking action of the hydrostatic head of the material 52 in the supplybin exerted over the duct areas, the material will bridgeacross the ductpassage, as at 55,'and plug the opening, thereby effectively sealing thepacker bin against escape through the infeed duct of the pressurized airin the packer bin.

Accordingly as the material 51 in the packer bin continues to dischargethrough the spout 13 into the bag 14, the level of the material in thepacker bin will continue to fall, as at 56, FIG. 3, and thence as at 57of FIG. 4, at which level the bag 14 is filled to the preselected weightor desired weight. At this stage the clamp 17 is actuated to close offthe spout 13 and valve 25 is actuated to connect the disseminatorpipeline 20 to the atmospheric exhaust 26, as indicated by the arrow onvalve 24, FIG. 5. This releases the air pressure in the packer bin,whereupon the material bridge 55, FIGS. 2 and 3, in the infeed duct 32,collapses, causing the material 52 in the supply bin to flow undergravity through the infeed duct 32 into the packer bin 10, as at 58,thus refilling the packer bin, as shown at 51 in FIG. 2. This cycle ofoperation is then repeated for each successive bag to be filled.

Referring to FIG. 6, the infeed duct 32, may be provided with a plug 60of conforming contour and secured to an adjusting rod 61, for verticalup or down' adjustment as indicated by the arrow, the adjustment beingsuch for any given loose aggregate material being packaged, as toestablish the optimum infeed aperture for assuring the material bridgingaction in the duct during discharge of the packer bin.

Referring to FIG. 7, the base of the supply bin may be provided with afluidizing air pad, mounted at 62 adjacent the bin discharge outlet forpurposes above explained, the pad being backed by an air chamber 63,supplied with air under pressure, from line 64, having interposedtherein a valve 65, for adjusting the flow being on and ofi or betweenhigh or low flow rates, as desired.

Referring to FIG. 8, the infeed duct 32 may optionally be provided witha mechanical closure gate 66, which during the filling cycle ismaintained in the open position shown until the material bridge 55 hasformed, and may thereupon be closed for the remainder of the packer bindischarge. In this way it is assured that the air seal in the infeedduct will be maintained during such discharge, should the materialbridge collapse due to abnormal operation. It will be observed in thisconnection that the material bridge 55 forms above and is spaced fromthe gate 66, so that the latter may be actuated without contacting theaggregate material. Hence if this material is of an abrading characteror comprises relatively large pellets, no injury to or jamming of thegate can occur in closure, as in the operation of force flow packers asheretofore constructed and operated.

What is claimed is:

1. Apparatus for dispensing and packaging loose aggregate material,comprising: a closed dispensing bin having a lower dispensing outlet andclosure means therefore releasable for dispensing said material, asupply bin disposed above said dispensing bin and opening at its baseinto a duct projecting in sealed relation through a top opening in saiddispensing bin, means for injecting air under pressure into at least theupper portion of said dispensing bin and means connected thereto fordispersing said air in said dispensing bin, for dispensing said materialfrom said dispensing bin through said outlet, and said duct being ofdimensions and aperture such that during pressurization of saiddispensing bin by said injected air, and with said supply bin filledwith said material to the extent of forming a static head of materialfor maintaining a downward force over said duct area of at least onehundred pounds, the said material in said supply bin bridges across andplugs said duct and prevents flow of said material into said dispensingbin.

2.1Apparatus for dispensing and packaging loose aggregate material,comprising: a closed dispensing bin having a lower dispensing outlet andclosure means therefor releasable for dispensing said material, a supplybin disposed above said dispensing bin and opening at its base into aduct projecting in sealed relation through a top opening in saiddispensing bin, means for injecting air under pressure into at least theupper portion of said dispensing bin and means connected thereto fordispersing said air in said dispensing bin, said dispersing meanscomprising a tubular disseminator disposed substantially coaxially ofsaid dispensing bin and perforated throughout its length andcircumference, for dispensing said material from said dispensing binthrough said outlet, and said duct being of dimensions such that duringpressurization of said dispensing bin by said injected air, and withsaid supply bin filled with said material to the extent of forming astatic head of material for maintaining a downward force over said ductarea of at least one hundred pounds, the said material in said supplybin bridges across and plugs said duct and prevents flow of saidmaterial into said dispensing bin.

3. Apparatus for dispensing and packaging loose aggregate material,comprising: a closed dispensing bin having a lower dispensing outlet andclosure means therefor releasable for dispensing said material, a supplybin disposed above said dispensing bin and opening at its base into aduct projecting in sealed relation through a top opening in saiddispensing bin, means for injecting air under pressure into at least theupper portion of said dispensing bin and means connected thereto fordispersing said air in said dispensing bin, said dispersing meanscomprising a tubular disseminator disposed substantially coaxially ofsaid dispensing bin and perforated lengthwise and circumferentially,said disseminator being also disposed with its base adjacent saiddispensing outlet, for dispensing said material from said dispensing binthrough said outlet, and said duct having an aperture area of about 30to square inches and a length of about 6 to 12 inches, and being ofdimensions such that during pressurization by said dispensing air ofsaid dispensing bin by said injected air, and with said supply binfilled with said material to the extent of forming a static head ofmaterial for maintaining a downward force over said duct area of atleast one hundred pounds, the said material in said supply bin bridgesacross and plugs said duct and prevents flow of said material into saiddispensing bin.

4. Apparatus for dispensing and packaging loose aggregate material,comprising: a closed dispensing bin having a lower dispensing outlet andclosure means therefor releasable for dispensing said material, a supplybin disposed above said dispensing bin and opening at its base into aduct projecting in sealed relation through a top opening in saiddispensing bin, means for injecting air under pressure into the upperportion of said dispensing bin and means connected thereto fordispersing said air in said dispensing bin, said dispersing meanscomprising a tubular disseminator disposed substantially coaxially ofsaid dispensing bin and perforated throughout its length andcircumference, for dispensing said material from said dispensing binthrough said outlet, and said duct being of dimensions such that duringpressurization by said dispersing air of said dispensing bin by saidinjected air, and with said supply bin filled with said material to theextent of forming a static head of material for maintaining asubstantial pressure over said duct area the said material in saidsupply bin bridges across and plugs said duct and prevents flow of saidmaterial into said dispensing bin, means for injecting fluidizing airunder pressure through the base of said dispensing bin adjacent saiddispensing outlet, and releasable, mechanical closure means for saidduct.

5. Apparatus for dispensing and packaging fluidizable, loose aggregatematerial, comprising: a closed bin having a lower dispensing outlet,said outlet having normally closed valve means releasable for dispensingsaid material, a pressurized gas injection and dispersing means forfluidizing said material, valve means for controlling said injection anddispersing means, said bin having normally closed venting means operableto vent said bin to atmospheric pressure, a hopper containing materialtherein being positioned adjacent said bin, an infeed conduitinterconnecting said hopper with said bin, said conduit being adapted toform a material-gate, plugging said conduit when said air injection anddispersing means are fluidizing said material and when said outlet valvemeans are released for dispensing said material, said infeed conduitbeing adapted to pass material therethrough when said air injection anddispersing means are closed and when dispensing outlet means are closedand when said venting means are open.

6. Apparatus for dispensing and packaging fiuidizable, loose aggregatematerial, comprising: a closed bin having lower dispensing outlet means,pressurized air injection and dispersing means for pressurizing said binand fluidizing said material, a hopper containing said materialpositioned above said bin, an infeed conduit interconnecting said hopperwith said bin for the flow of said material therethrough, said infeedconduit being provided with a substantially smaller cross-sectionalpassage area than said bin, said infeed conduit being adapted to form amaterialgate therein, plugging said conduit, when a substantial weightof material is contained within said hopper and when said injection anddispersing means are fluidizing said material in said bin.

7. Apparatus for dispensing and packaging loose aggregate material,comprising: a closed dispensing bin having a lower dispensing outlet andclosure means therefor releasable for dispensing said material, a supplybin disposed above said dispensing bin and opening at its base into aduct projecting in sealed relation through a top opening in saiddispensing bin, means for injecting air under pressure into at least theupper portion of said dispensing bin and means connected thereto fordispersing said air in said dispensing him, said duct being ofdimensions such that during pressurization by said dispersing air ofsaid dispensing bin by said injected air, and with said supply binfilled with said material to the extent of forming a static head ofmaterial for maintaining a substantial pressure over said duct area, thesaid material in said supply bin bridges across and plugs said duct andprevents fiow of said material into said dispensing bin, and mechanicalclosure means for said duct.

8. A method of packaging loose aggregate material, comprising: filling asupply bin to a substantial height with said material, introducing saidmaterial from the lower portion of said supply bin into an elongatedinfeed conduit having reduced passage area, intermittently passing saidmaterial from said conduit into a closed dispensing bin having increasedpassage area, intermittently introducing dispersing air into anelongated central portion of said dispensing bin at a plurality ofopenings to pressurize said dispensing bin and fiuidize the material insaid dispensing bin, while simultaneously causing to form a releasablematerial-gate within said conduit by pressurization by said dispersingair of said dispensing bin to prevent flow of said material into saiddispensing bin, and while simultaneously discharging said fluidizedmaterial from said dispensing bin through an outlet opening into apackaging container.

9. A method of packaging loose aggregate material, comprising: filling asupply bin to a substantial height with said material, introducing saidmaterial from the lower portion of said supply bin into an infeedconduit having reduced passage area, intermittently passing saidmaterial from said infeed conduit into a closed dispensing bin havingincreased passage area, intermittently introducing dispersing air intosaid dispensing bin to cause said material in said conduit to bridgeacross and plug said conduit and substantially prevent fioW of saidmaterial into said dispensing bin, thence closing mechanical valve meansin said infeed conduit to completely prevent flow of said material intosaid dispensing bin, and discharging said material from said dispensingbin through an outlet opening into a packaging container.

References Cited by the Examiner UNITED STATES PATENTS 182,097 9/1876Barton 222373 951,754 3/1910 Buzzell et a1 302 1,271,107 7/1918 Weller222-493 X 2,032,367 3/1936 Kennedy et al 302-53 2,219,208 10/1940 Knight222193 2,851,401 9/1958 Payne 30263 X 2,936,994 5/1960 Lau 141'-68 X3,073,401 1/1963 Zenke.

FOREIGN PATENTS 671,667 5/1952 Great Britain.

LAVERNE D. GEIGER, Primary Examiner.

LOUIS J. DEMBO, Examiner.

D. MAXSON, H. BELL, Assistant Examiners.

8. A METHOD OF PACKAGING LOOSE AGGREGATE MATERIAL, COMPRISING: FILLING ASUPPLY BIN TO A SUBSTANTIAL HEIGHT WITH SAID MATERIAL, INTRODUCING SAIDMATERIAL FROM THE LOWER PORTION OF SAID SUPPLY BIN INTO AN ELONGATEDINFEED CONDUIT HAVING REDUCED PASSAGE AREA, INTERMITTENTLY PASSING SAIDMATERIAL FROM SAID CONDUIT INTO A CLOSED DISPENSING BIN HAVING INCREASEDPASSAGE AREA, INTERMITTENTLY INTRODUCING DISPERSING AIR INTO ANELONGATED CENTRAL PORTION OF SAID DISPENSING BIN AT A PLURALITY OFOPENINGS TO PRESSURIZE SAID DISPENSING BIN AND FLUIDIZE THE MATERIAL INSAID DISPENSING BIN, WHILE SIMULTANEOUSLY CAUSING TO FORM A RELEASABLEMATERIAL-GATE WITHIN SAID CONDUIT BY PRESSURIZATION BY SAID DISPERSINGAIR OF DISPENSING BIN TO PREVENT FLOW OF SAID MATERIAL INTO SAIDDIPENSING BIN, AND WHILE SIMULTANEOUSLY DISCHARGING SAID FLUIDIZEDMATERIAL FROM SAID DISPENSING BIN THROUGH AN OUTLET OPENING INTO APACKAGING CONTAINER.